The name Kefir comes from the Turkish word keyif, which refers to the "good feeling" a person gets after they have drunk it.
Kefir has been popular in parts of Europe and Asia for many years but has only recently started gaining popularity in the United States, due to the growing interest in probiotics and gut health.
What is kefir?
Kefir is made using bacteria, giving it probiotic qualities. Probiotics are attributed with supporting healthy digestive functions.
While yogurt is the fermentation of bacteria in milk, kefir is a combination of bacteria and yeast fermentations. The combination of bacteria and yeast is called "kefir grain."
Kefir grains are not typical grains, such as wheat or rice, and do not contain gluten. Milk is combined with the kefir grains and stored in a warm area to "culture," producing the kefir beverage.
Kefir has a tart and tangy flavor, and a consistency similar to a drinkable yogurt. Due to the fermentation process, kefir may taste slightly carbonated.
Many of kefir's health benefits are attributed to its probiotic content. Probiotics, or "good bacteria," are living organisms that can help maintain regular bowel movements, treat certain digestive conditions, and support the immune system.
While kefir is typically made from cow's milk, it can also be produced from the milk of other animals, such as goats or sheep, or from non-dairy milks.
Kefir made from cow's milk is available in non-fat, low-fat, and whole milk varieties.
Kefir is also available in plain and flavored varieties.
Kefir consumption is still being researched, but the potential benefits include:
1. Blood sugar control
Participants who consumed the kefir had significantly lower fasting blood sugar levels than those who consumed the conventionally fermented milk.
Participants in the kefir group also had decreased hemoglobin A1c values, which are a measurement of blood sugar management over 3 months.
2. Lower cholesterol
A 2017 study looked at changes in cholesterol levels among women drinking low-fat milk or kefir. The participants drank either 2 servings a day of low-fat milk, 4 servings a day of low-fat milk, or 4 servings a day of kefir.
After 8 weeks, those who drank kefir showed significant decreases in their total and their "bad cholesterol" levels compared to those who drank only 2 servings per day of low-fat milk. Participants who consumed 4 servings per day of low-fat milk also had lowered cholesterol levels.
The probiotics in kefir may play a role in how much cholesterol the body absorbs from food. They may also affect how the body produces, processes, and uses cholesterol.
3. Increased nutrition
4. Improved lactose tolerance
People with lactose intolerance may be able to consume kefir without experiencing symptoms, as the bacteria present in kefir break down much of the lactose.
The leading brand of kefir in the U.S. claims to be 99 percent lactose-free.
A small study in 2003 concluded that the consumption of kefir improved lactose digestion over time, and could potentially be used to help overcome lactose intolerance. It noted that flavored kefir produced more adverse symptoms that plain kefir, probably due to added sugars in the flavored product.
5. Improved stomach health
Kefir may be able to help treat digestive issues, such as diarrhea or lactose intolerance.
The stomach contains both good and bad bacteria. Maintaining a balance between them is an important part of keeping the stomach healthy. Diseases, infections, and some medications, such as antibiotics, can upset this balance.
Probiotics are similar to the good bacteria found naturally in the digestive tract and may help maintain a healthy balance.
6. Healing properties
Laboratory studies have shown kefir may have antibacterial and antifungal properties, although more investigation is needed.
A 2016 review reported that kefir lessened the severity of symptoms in mice infected with a parasite. Another review demonstrated beneficial effects of kefir on mice for wound healing and reduced tumor growth.
7. Weight control
Making kefir at home
Kefir is made using the fermentations of yeast and bacteria. This mixture creates kefir grains, which can be combined with milk to create a tangy drink.
A person can make kefir at home in a clean environment. Utensils, cooking equipment, and a person's hands should be washed thoroughly with soap and water before starting.
You will need:
- active kefir grains
- your preferred type of milk
- a glass jar
- a paper coffee filter or cheesecloth
- a rubber band
- a silicone spatula or wooden spoon (non-metal stirring utensil)
- a non-metal mesh strainer
Combine 1 teaspoon of kefir grains for every cup of milk into a glass jar. Cover the jar with the paper coffee filter and secure with a rubber band. Store the jar in a warm place around 70°F for 12-48 hours, depending on your taste and the warmth of the room.
Once the milk has thickened and has a tangy taste, strain the kefir into a storage container. Cover tightly and store for up to 1 week.
There are a few tips to be aware of when making kefir at home:
- Exposure to metal can weaken the kefir grains, so avoid metal utensils.
- Temperatures above 90 °F can cause the milk to spoil.
- Keep the jar away from direct sunlight.
- The strained kefir grains can be kept to make new batches.
- Shake it if it starts to separate while being stored.
- To make a fruit-flavored kefir, chop up fruit and add it to the strained kefir. Let it sit for an additional 24 hours. Re-strain if desired.
How to use kefir
Kefir can be used in many of the ways milk and yogurts is used.
It can be drunk as a beverage, used as the blending liquid in a smoothie, or poured over cereal or oats. Kefir can also be used in baked goods, soups, dips, or salad dressings, though heat may significantly decrease probiotic concentration.
Risks and considerations
Kefir is safe to consume, but a person must consider certain factors before adding it to a regular diet.
While people who are lactose intolerant may be able to drink kefir without symptoms, others with a milk allergy should not consume kefir made from dairy milk, as it can cause an allergic reaction.
Since kefir is made from milk, it contains some sugar. Some pre-packaged, flavored kefirs have high amounts of added sugar.
People with diabetes should be especially careful to read the label and stick to plain varieties without added sugar.
When made traditionally, kefir may contain trace amounts of alcohol. Many commercial brands of kefir are alcohol-free.